Hypodermic syringe



Sept. 21 ,1926.

G. N. HEIN HYPODERMIC SYRINGE Filed August 6, 1925 INVENT R m Mal 9.951212.-

ATTORNEY Patented Sept. 21, 1926 t it H UNITED STATES GEORGE u. Ham, on SAN rmmcrsco, CALIFORNIA HYPODERMVIC SYRINGE.

Application filed-August 6, 1925. serial m. 43,504.

This present invention relates to a, hy- Podermic y n e of en mw sly 9P- erated or pump type by which the fluid'may be injected in a continuous stream intothe body of the patient froma relatively large pp y a v Among the objects of this in'ventionjare to enable the injection of relatively 'large volumes offluidby the aid; of anhypo dermic syringe without necessitating the; insertion and removal of the'needle from the body of the patient at each time the syringe barrel is emptied; to provide a construction; enabling an operatorby the movement of the fingers of one hand to-imparta pump action to the; relative par-ts oi the apparatus; to enable substantially continuous injection. A further object is to; provide a structure by theme of which the fluid rnay be removed; from its original container and injected into the patient without-exposure ,to-

the atmosphere, thereby reducing contamination, 4 7

Another object is the provision of a; novel form of-piston and check valve.

The invention cons sts primarily in, a

structure wherein there is provided a; tubular piston surroundedi by a; tubularguide,

the piston at one; end mounting; a packing andcheck end valve cooperatingiwith the coupling nut constituting the needle mounting, and with the piston fihere being eo operatively associated acylinder capable of telescopicaction between the piston and inner guide wall, there beingprovided at the upper end of; thepiston a; packing and at the upper end of the cylinder a packingand checkvalve controlling the passage; of fluid into the upper end of the cylinder by its reciprocation; i 5 With the above mentioned and other; objects in view, the inventionoonsists primarily in the structure herein-afterdescribedgthe preferred embodiment of which is illustrated in the accompanying drawings, wherein; I

Fig. 1 is. a view in vertical section; ot the preferred embodiment of the invention illustrating particularly packing and checkvalves positioned respectively at the upper end of the cylinder and at the lower endof I the piston and the packing positioned at the upper end of, the piston. I

Fig. 2- is a View in, elevation of the. guide illustrating articularl the p in mp1 at .theoy-linder and the finger-grip member.

Fig; is a-yiew v'ertic'al se'ction oi a structure, wherein 1S illustrated. a niodified cylinder closing plug- 7 Fig} is a vie I in} enlargedv detail or: the check valve'at the inlet end ofthe cylinder. Fig, 5 is an enlarged detail-view ofthe check valve at the discharge end of the piston. v. v I

In the drawings wherein like characters of reference designatecorresponding pants, 1 indicates a tubula'r guide open at it's'j op- PQSllZQ ends and at one end provided with oppositely disposed finger, engaging loops 2.

v The other endof the guide i'spiovided with form of cylinder associated, with tubular sleeve preferably'of rubber, the side-walls of which constitute'a, packing o, and check valve 12 to control the direction of passage offluid 'throughchannel 6.

Threaded to the end of the piston 6 proje'cting' through the threaded bore 3 is a vtubular needle base 14: mounting a needle 13.

The head Q'at the lower end oi the piston 6 projects into a pocketor recess 15 in the base '14 and the periphery of. the packing 10 beats tightly against. the wall surface thereof with the skirt 12 overlying the tapered portion to open toward the upper end; of the hypodermic needle 17;

A cylinder 19. open at its lowerend is positioned over the'pi'ston 6 to. telescope'in the space between the piston and thezinner surface of the guide 1. This cylinder in Fig. 1 is preferably constructed of metal) and at its upper end is. preferably threaded at 20 to a tubular [closing plug 21 the end of which mounts a finger loop or grip 22 and the bore 23 of said plug extends angularly through: the side wall thereof as illustrated. The plug 21 is provided with an headed extension 24 similar to the extension 9 and over the same is stretched an elastic .cup or hood, the side walls of which engage the inner surface of the cylinder and form a packing 25. The lower end 25 of the hood is in tight contact with the end of extension 24 and is ported as at 26 out of register with the end of ported bore 23 providing a check valve controlling the direction of fluid passage through bore 23. This end 25 bulges inw'ardly toward the upper end of the piston 6 on a relatively separating movement being imparted to the piston and cylinder, at which time the check valve 12 is unseated and operates to seat on a relatively telescoping movement beingimparted to the piston and cylinder, at which time the valve 12 opens. The cylinder at its lower end is formed with a lip 27 which'is adapted to engage a spring clip 28 carried by the guide 1 nearv its upper open end, the cooperation of the two precluding accldental separation of the piston and cylinder during the pumping of the fluid, the member 28 admitting of releasing, however, to admit of the separation of the parts when it is so desired.

In the structure illustrated in Fig. 8, the cylinder 19 is of glass construction, and to attach the same to the closing plug 21 the cylinder is preferably provided with an attaching bead 29 adapted to contact with the packing 30 in the base of the groove within the member 21, a ferrule slipped over the cylinder 19 engaging the bead and threadably uniting the same in a detachable main ner to the closing plug 21.

The device being assembled as in the drawings, it will be observed that a relative pumping action or reciprocating movement being imparted to the members1-6 as a unit and 19 as another unit, that fluid will be drawn inwardly through the bore 28, enter the expanding chamber of the cylinder 19. during one cycle of operation, and passing through the piston 6 and from the needle 1'? dining the contraction of the cylinder chamber 1.9 on a succeeding cycle of operation, thus en abling a relatively continuous flow of fluid to be withdrawn from a supply and injected into a patient without the necessity of withdrawing the needle from the flesh of the patient.

The check valves normally by the contraction of the elastic material, seal the outlet of fluid passing through the valves.

I claim: I 1. In a hypodermicsyringe, a tubular pis- .der and the guide.

ton provided with a packing at one end and a check-valve for controlling the fluid flow through the piston, a tubular guide openat one end, surrounding the piston, and within which the piston is mounted, a tubular cylinder provided with a fluid inlet bore at one endand for positioning over said piston to reciprocate thereover between the piston and theguide :with the piston packing engaging the inner cylinder wall, a check-valve openin into the cylinder for controlling the fluid passing through said bore, and finger-grips associated with the cylinder and guide.

2. In a hypodermic syringe, a tubular piston provided with a packing surrounding one end, a check-valve associated'withthe opposite end, a tubular guide concentrically within which the piston is positioned and within which the pistonis detachably secured,'a cylinder mounted to reciprocattebeone end, a check-valve associated with the opposite end, a tubular guide concentrically within which the piston is positioned and through the end of which the check-valve end of the piston extends, a needle and needle base for attachment to the end of the piston extending through the guide, a tubular cylinder mounted to reciprocate over the piston and within the cylinder with the surface of the piston packing engaging the: cylinder wall, a channeled closure for the upper end of the cylinder, a check-valve associated with the closure and opening into the cylinder, and finger-grips associated with the cylin- 4. In combination with a piston provided with a here, an elastic member stretched over one end thereof with its wall surface due to the elasticity of the member normally in contact with the piston wall sealing said bore, said elastic member provided with a normally open aperture :in its wall surface offset from the end of said piston bore,

wherebyon a pressure in said bore said wall surface of said elastic member separating said bore and'aperture is distorted'to admit of fluid passage from the bore through the aperture. I

5. Ina hypodermic syringe, the combination of a channeled piston formedat its outer end with a reduced extension through the side of which the channel of said piston opens; a needle-carrying member fitted to the end of sa1d piston, sa1d memberhaving a pocket in which the reducedextension of the piston is housed; and anelastic'sleevefitted upon said extension a portion of said sleeve serving as a packing between said extension and the needle-carrying member, and another portion of the sleeve covering the piston- 5 channel opening and serving as a check valve.

6. In a hypodermic syringe, the combination of a channeled piston formed at its outer said member having a pocket in which the 10 reduced extension of the piston is housed; and an elastic sleeve fitted upon said extension a portion of said sleeve serving as a packing between said extension and the needle-carrying member.

In testimony whereof I have signed my name to this specification.v

GEORGE N. HEIN. 

